Safety and efficacy of the flow diverter device for treating middle cerebral artery aneurysms of the proximal (M1) segment related to the lenticulostriate arteries: A single-center experience.

BACKGROUND: Experience using flow diverter devices (FDDs) to treat proximal (M1) middle cerebral artery aneurysms associated with the lenticulostriate artery (M1A-LA) remains limited. This study aimed to examine the efficacy and safety of an FDD to manage M1A-LA. METHOD: Patients with M1A-LA who received FDD treatment at a single center were included in the analysis. Data on the baseline characteristics, postoperative conditions, and follow-up results of the participants were recorded and analyzed. The aneurysms were categorized into three subtypes based on morphology and location. Aneurysms confined to the M1 segment were categorized as subtype A. Those extending to the M2 segment were classified as subtype B. Aneurysms designated as subtype C were confined to the M1 segment but with another independent aneurysm in the distal artery and the presence of healthy vessels between the two. Subgroup analyses were conducted on these subtypes and aneurysm sizes. To assess the consistency of follow-up results, Cronbach's kappa/alpha was used to calculate inter-rater variability. Somers's D coefficient was used to assess the correlation between each subgroup and the imaging outcomes; Fisher's exact test was used to compare the variability among the subgroups. RESULT: The cohort comprised 11 patients. Their Modified Rankin Scale scores between the perioperative and follow-up periods did not differ. During the follow-up period, four patients had completely occluded aneurysms, and five patients had partial occlusions. The remaining patients did not present with changes in their aneurysms. The kappa coefficient was 0.864 (p < 0.001). M1A-LA was divided into subtypes A, B, and C. Subtype A (defined as an aneurysm completely located in the M1 segment) had a higher complete occlusion rate than that of subtypes B and C, Somers's D R/C correlation coefficient was 0.553, with a 95% confidence interval of 0.1229-0.9823 (p = 0.009). The radiographic follow-up findings were not significantly correlated with the size of the aneurysm (p = 0.121) or the use of coiling (p = 0.903). No significant differences in subtypes (p = 0.264), aneurysm size (p = 0.657), or coiling use (p > 0.999) were observed. CONCLUSION: FDDs were safe and possibly effective against M1A-LA. However, they were not as effective as for intracranial aneurysms in other locations. FDDs are a satisfactory treatment option for M1A-LA, particularly for subtype A aneurysms.

Delayed leukoencephalopathy following non-coil embolization flow diverter stent deployment for an intracranial aneurysm.

This report examines delayed leukoencephalopathy as a postoperative complication after the use of flow diverter (FD) devices for endovascular cerebral aneurysm treatment. A case involving a 78-year-old female treated with a pipeline embolization device for a left internal carotid artery aneurysm is presented. Despite adherence to dual anti-platelet therapy, the patient developed intermittent headaches and memory issues 3 months post-operation. MRI revealed T1-enhancing foci and T2 hyperintense signal abnormalities in the left cerebral hemisphere, without new ischemic lesions, indicating potential embolic events or foreign body reactions. Following aphasia, a change from clopidogrel to prasugrel and the initiation of steroid pulse therapy led to the resolution of symptoms and MRI abnormalities over 6 months. This case underscores the reversibility of delayed leukoencephalopathy with appropriate intervention.

Comparison Between the Efficacy of a Flow Diverter and Interventional Trapping with Bypass in the Treatment of Unruptured Large- or Giant-Sized ICA Aneurysms.

OBJECTIVE: Management of large- or giant-sized internal carotid artery aneurysms (LICAAs) remains challenging. Whether a flow diverter device (FDD) or interventional trapping with extracranial-intracranial bypass (ITB) is better, remains unclear. METHODS: We conducted a multicenter retrospective analysis of unruptured LICAA patients treated with FDD or ITB at 3 medical centers. Both the effectiveness and safety results of FDD and ITB were compared. RESULTS: In total, 101 aneurysms in 95 patients treated with FDDs and 36 aneurysms in 36 patients managed with ITBs were included (September 2014-June 2021). There was no significant difference between the groups in the complete obliteration rate 1 year after surgery (P = 0.101). There were 2 relapse cases (2.0%) and 4 retreated cases (4.0%) in the FDD group and 1 relapse case (2.8%) and 2 retreated cases (5.6%) in the ITB group. Neither the relapse rates nor retreat rates between groups were significantly different. The neurological morbidity rates were 4.0% (4/101) and 2.8% (1/36) in the FDD group and ITB group, respectively, and were not significantly different. There was 1 mortality case in each group, and the mortality rates were not significantly different (P = 0.443). Both the perioperative and overall (perioperative plus long-term) complication rates in the FDD group were significantly lower than those in the ITB group (P = 0.033, P = 0.039). CONCLUSIONS: FDD had comparable surgical efficacy and a significantly lower postoperative complication rate to traditional ITB. FDD might be preferable to ITB as a treatment modality for LICAA.

Flow Diverter Device-Assisted Coiling Treatment for Cerebral Blister Aneurysm: A Single-Center Study.

Although endovascular treatment is a promising approach, blood blister-like aneurysms (BBAs) still present treatment challenges. This study aimed to assess the effectiveness and safety of flow diverter device-assisted coiling (FDDAC) for the treatment of BBAs, which are broad based and friable with a high rebleeding risk. Eight patients (five females and three males) who presented with subarachnoid hemorrhages (SAH) due to BBA ruptures between May 2020 and May 2022 were retrospectively enrolled. All patients were treated by flow diverter device (Tubridge) adjunctive coil embolization using a semi-deploying technique. The demographic information, angiographic data, interval between admission and treatment, materials, therapy, clinical outcomes (including periprocedural and intraprocedural mortality and morbidity), and follow-up results of all patients were reviewed. The mean age of the patients with BBAs was 48.5 years (range 31-62 years); aneurysm sizes ranged from 2.2 × 1.7 mm to 4.6 × 3.2 mm, and the median Hunt-Hess score was 3. All aneurysms were completely closed at follow-up, and all 8 patients had excellent clinical outcomes (modified Rankin scores = 0-2) at discharge. Angiograms showed complete aneurysm occlusion after 6 months to 1 year. In addition, there were no cases of re-rupture, re-treatment, or recurrence of the aneurysms. FDDAC is safe to use in patients with BBAs and provides an alternative treatment option for this disease.

Efficacy and safety of flow diverters in posterior circulation aneurysms and comparison with their efficacy in anterior circulation aneurysms: A systematic review and meta-analysis.

PURPOSE: We aimed to assess the efficacy and safety of flow-diverter stents (FDs) in the management of posterior circulation cerebral aneurysms and compare FD efficacy between anterior and posterior circulation aneurysms. METHODS: We searched the PubMed, Scopus, Cochrane, and Web of Science databases for relevant studies through March 2020. Studies assessing FDs for posterior circulation aneurysms that included ≥20 treated aneurysms were included. Moreover, the studies compared FD efficacy between anterior and posterior circulation aneurysms were included. Data regarding angiographic aneurysmal occlusion, procedural complications, mortality, and morbidity were extracted and pooled in a random-effects meta-analysis model. RESULTS: Fourteen studies with a total of 659 patients and 676 posterior circulation aneurysms were included. The pooled rate of aneurysmal occlusion at long-term angiographic follow-up was 78% [95% confidence interval (CI), 71-85]. The pooled rates of intraparenchymal hemorrhage, ischemia, and procedure-related mortality and neurological morbidity were 2%, 8%, 7%, and 6%, respectively. Complete occlusion occurred in 82.4% of the posterior circulation aneurysm subgroup and 77.5% of the anterior circulation aneurysm subgroup. The difference was not significant (relative risk 1.01; 95% CI, 0.86-1.19; p = 0.91). Regression analysis showed that elderly patients and females had higher morbidity. CONCLUSION: Posterior circulation aneurysms can be effectively treated with FDs with comparable occlusion rates to those in anterior circulation aneurysms. However, periprocedural complications are not negligible.

Flow diverter device placement for cerebral aneurysm is not effective for the patient with parent artery occlusion for contralateral aneurysm.

PURPOSE: There have been many reports on the risks of enlargement and rupture of residual aneurysms and de novo aneurysm formation in the contralateral internal carotid artery after parent artery occlusion (PAO). In the present study, we investigated the efficacy of flow diverter device placement (FDDP) for the treatment of contralateral internal carotid artery aneurysms after PAO. METHODS: After 11 patients, who had bilateral large or giant internal carotid aneurysms, were treated for either side with PAO or FDDP, they underwent FDDP for residual lesions in our hospital between October 2015 and June 2018. The patients were divided into two groups, depending on the prior procedure: PAO or FDDP. The embolic state after subsequent FDDP was evaluated by angiography. The embolic state was graded using the O'Kelly Marotta scale. Patients' characteristics and the embolic state of intracranial aneurysms after FDDP were compared between the two groups. RESULTS: Comparing patients' characteristics between the PAO group and FDDP group, statistically significant differences were observed in laterality of the lesions and the interval between prior treatment and FDDP for residual aneurysms (p < 0.05). The embolic state at the one-year follow-up revealed that there could be significantly sufficient embolisation in the FDDP group (p < 0.05). CONCLUSION: When FDDP is performed for the contralateral lesion after PAO treatment, it is difficult to attain sufficient embolisation of intracranial aneurysms because haemodynamic load in this procedure is large compared to that in a regular FDDP.

Expanding Indications for Flow Diverters: Distal Aneurysms, Bifurcation Aneurysms, Small Aneurysms, Previously Coiled Aneurysms and Clipped Aneurysms, and Carotid Cavernous Fistulas.

Flow diverter devices have gained wide acceptance for the treatment of unruptured intracranial aneurysms. Most studies are based on the treatment of large aneurysms harboring on the carotid syphon. However, during the last years the "off-label" use of these stents has widely grown up even if not supported by randomized studies. This review examines the relevant literature concerning "off-label" indications for flow diverter devices, such as for distal aneurysms, bifurcation aneurysms, small aneurysms, recurrent aneurysms, and direct carotid cavernous fistulas.

Patency of Posterior Circulation Branches Covered by Flow Diverter Device: A Hemodynamic Study.

Objective: Flow diverter devices are increasingly used in the treatment of posterior circulation aneurysms, sometimes necessarily involving ostia of side branches and perforators. The aim of this study was to identify the hemodynamic influence of flow diverters on side branches and perforators of the posterior circulation. Methods: We performed a retrospective study of consecutive patients treated by a flow diverter device for posterior circulation aneurysms with anterior inferior cerebellar artery (AICA) or posterior inferior cerebellar artery (PICA) involvement. Computational fluid dynamics (CFD) were used to discern hemodynamic changes of branches after deployment of the flow diverter. Results: We studied 18 branches from 17 patients (mean age, 50.72 ± 8.17 years). No branches were occluded on immediate angiography and later follow-up. Average flow velocity in aneurysms decreased from 0.077 ± 0.065 m/s to 0.025 ± 0.025 m/s (p < 0.01). Average flow velocity in branch ostia decreased from 0.29 ± 0.14 m/s to 0.27 ± 0.16 m/s (p = 0.189). The difference in flow velocity reduction ratio between aneurysms and branches was statistically significant (68.8 vs. 9.5%; p < 0.001). The mean pressure in branch ostia increased from 10,717.4 ± 489.0 to 10,859.0 ± 643.4 Pa (p < 0.01). Conclusion: While a flow diverter device is capable of slowing down aneurysmal inflow, it is unable to block the flow into branches and perforators when used in the treatment of posterior circulation aneurysms; flow velocity in branches even increased in some cases. With a low branch occlusion ratio, it may be acceptable to cover posterior circulation branches and perforators if unavoidable.

Reconstrucción endovascular de aneurisma intracraneal mediante dispositivo diversor de flujo Pipeline®. Reporte de 2 casos y revisión de la literatura / Endovascular reconstruction of intracranial aneurysm using a Pipeline® flow diversifier device

Resumen Introducción: Los aneurismas intracraneales son anomalías vasculares cerebrales con una prevalencia aproximada a nivel mundial del 2-3%. Son la principal causa de hemorragia subaracnoidea no traumática, el diagnóstico y tratamiento preventivo de esta entidad puede reducir considerablemente la morbimortalidad que de ella deviene. Con la aparición de nuevos dispositivos de terapia endovascular cerebral como los diversores de flujo se ha logrado ofrecer al paciente un procedimiento menos invasivo que no requiere cirugía convencional, y una importante reducción en el número de días de estancia intrahospitalaria y de recuperación, con alto grado de seguridad. El tratamiento endovascular para aneurismas intracraneales ha evolucionado sustancialmente en las últimas dos décadas, convirtiéndose en el tratamiento de elección en diversas situaciones clínicas. Reporte de caso: Caso 1: Varón de 62 años edad que ingresa a unidad hospitalaria después de sufrir un traumatismo craneoencefálico moderado con pérdida transitoria del estado de alerta y cefalea holocraneana. Se realizó una tomografía de cráneo simple y con contraste ante la sospecha de hemorragia subaracnoidea. Se evidenció la presencia de un aneurisma intracraneal en la arteria carótida interna izquierda, segmento comunicante posterior de 4 x 3 mm con cuello de 3 mm. Se realizó tratamiento mediante la colocación de dispositivo diversor de flujo Pipeline®, así como control angiográfico a los 3 meses post-tratamiento con una evolución satisfactoria. Caso 2: Mujer de 59 años de edad que acudió por presentar hemiparesia facial y brazo ipsilateral, con incremento gradual de la intensidad y duración. Se inició protocolo de estudio con resonancia magnética. Se evidenció la presencia de aneurisma intracraneal de 15 mm de diámetro en el segmento comunicante de la arteria carótida interna derecha y otro de 8 mm contralateral. Fue programada para colocación de dispositivo diversor de flujo Pipeline® con adecuada evolución. Conclusión: El uso de dispositivos diversores de flujo es una excelente alternativa para el tratamiento de aneurismas intracraneales incidentales, con importantes ventajas de costo-efectividad, reduciendo tiempos quirúrgicos, de estancia hospitalaria y de recuperación. Además de tener un porcentaje de curación superior al 95% a 5 años.

Abstract Introduction: Intracranial aneurysms are cerebral vascular anomalies with an approximate global prevalence of 2 to 3% and are the main cause of non-traumatic subarachnoid hemorrhage. Diagnosis and preventive treatment of this entity can considerably reduce morbidity and mortality. With the advent of new devices for cerebral endovascular therapy such as flow diverters, the patient now has the option of choosing a less invasive procedure, which does not require conventional surgery. This represents a significant reduction in the number of days of in hospital stay and recovery. The procedure has showed a high degree of security. The endovascular treatment for intracranial aneurysms has evolved substantially in the last two decades, and has become the treatment of choice. Case report: Case 1: A 62-year-old male was admitted in the hospital after a moderate cranioencephalic trauma with transient loss of conscious and a holocranial headache. A cerebral angiography was performed to rule out subarachnoid hemorrhage. The angiography showed an intracranial aneurysm. It was localized in left internal carotid-posterior communicating artery. The measures were of 4mm X 3mm with a 3mm neck. The treatment was performed with a pipeline flow-diverting device, as well as an angiographic control 3 months after the treatment with a satisfactory evolution. Case 2: A 59-year-old female patient with facial hemiparesis and ipsilateral arm, that showed a gradual increase in intensity and duration. A magnetic resonance study protocol was initiated and an intracranial aneurysm was observed in the communicating segment of the right internal carotid artery. The diameter of the aneurysmal sac was of 15 mm and also, a contralateral of 8 mm. Placement of a flow-diverting device was programmed. Conclusion: The use of flow-diverting devices is an excellent alternative for the treatment of incidental intracranial aneurysms, with important cost-effectiveness advantages, surgical time, hospital stay and recovery reduction. In addition to having a recovery percentage of 95% in 5 years.

Hemodynamic impacts of flow diverter devices on the ophthalmic artery.

BACKGROUND: Flow diverter devices are increasingly used for endovascular treatment of internal carotid artery aneurysms. Treatment of ophthalmic segment aneurysms with flow diverter devices also includes coverage of the ophthalmic artery but may result in complications. It is unclear, however, whether these devices mechanically block blood flow in the ophthalmic artery. Also unclear is the relationship between deployment of a flow diverter device and post-treatment occlusion. We studied hemodynamic changes in the ophthalmic artery after deployment of a flow diverter device to determine the relationship between those changes and post-stent occlusion of the artery. METHODS: We analyzed hemodynamic modifications in the ophthalmic artery in 21 patients (19 women, 2 men; mean age 53.43 ± 7.32 years) treated by a single pipeline embolization device. Patient-specific geometries were determined from three-dimensional digital subtraction angiography and the stenting process was simulated. Computational fluid dynamics technology was used to analyze the change in ophthalmic artery hemodynamics. We compared pre-treatment and post-treatment flow velocity of the ophthalmic artery. RESULTS: Among the 21 patients with aneurysms located in the ophthalmic segment, no ophthalmic artery occlusion was found during immediate or follow-up angiography. Post-stent flow velocity in the ophthalmic artery decreased from 0.35 ± 0.19 to 0.33 ± 0.20 m/s, with the difference not being statistically significant (P = 0.106). CONCLUSION: Our results showed no significant change in ophthalmic artery blood flow after pipeline embolization device deployment. Hence, post-stent occlusion of the ophthalmic artery could not be explained by reduced blood flow. Delayed thrombosis and neointimal formation maybe the keys to ophthalmic artery occlusion and need further investigation.

FRED Italian Registry: a multicenter experience with the flow re-direction endoluminal device for intracranial aneurysms.

OBJECTIVE: The introduction of flow-diverter devices (FDDs) has revolutionized the endovascular treatment of intracranial aneurysms. Here the authors present their Italian multicenter experience using the flow re-direction endoluminal device (FRED) in the treatment of cerebral aneurysms, evaluating both short- and long-term safety and efficacy of this device. METHODS: Between February 2013 and December 2014, 169 consecutive aneurysms treated using FRED in 166 patients were entered into this study across 30 Italian centers. Data collected included patient demographics, aneurysm location and characteristics, baseline angiography, adverse event and serious adverse event information, morbidity and mortality rates, and pre- and posttreatment modified Rankin Scale scores, as well as angiographic and cross-sectional CT/MRI follow-up at 3-6 months and/or 12-24 months per institutional standard of care. All images were reviewed and adjudicated by an independent core lab. RESULTS: Of the 169 lesions initially entered into the study, 4 were later determined to be extracranial or nonaneurysmal by the core lab and were excluded, leaving 165 aneurysms in 162 patients treated in 163 procedures. Ninety-one (56.2%) patients were asymptomatic with aneurysms found incidentally. Of the 165 aneurysms, 150 (90.9%) were unruptured. One hundred thirty-four (81.2%) were saccular, 27 (16.4%) were fusiform/dissecting, and the remaining 4 (2.4%) were blister-like. One hundred thirty-seven (83.0%) arose from the anterior circulation.FRED deployment was impossible in 2/163 (1.2%) cases, and in an additional 4 cases (2.5%) the device was misdeployed. Overall mortality and morbidity rates were 4.3% and 7.3%, respectively, with rates of mortality and morbidity potentially related to FRED of up to 2.4% and 6.2%, respectively. Neuroimaging follow-up at 3-6 months showed complete or nearly complete occlusion of the aneurysm in 94% of cases, increasing to 96% at 12-24 months' follow-up. Aneurysmal sac shrinkage was observed in 78% of assessable aneurysms. CONCLUSIONS: This preliminary experience using FRED for endovascular treatment of complex unruptured and ruptured aneurysms showed a high safety and efficacy profile that is comparable to those of other FDDs currently in use.

Flow diverter devices in ruptured intracranial aneurysms: a single-center experience.

OBJECTIVE In this single-center series, the authors retrospectively evaluated the effectiveness, safety, and midterm follow-up results of ruptured aneurysms treated by implantation of a flow diverter device (FDD). METHODS The records of 17 patients (12 females, 5 males, average World Federation of Neurosurgical Societies score = 2.9) who presented with subarachnoid hemorrhage (SAH) due to the rupture of an intracranial aneurysm treated with an FDD were retrospectively reviewed. Of 17 ruptured aneurysms, 8 were blood blister-like aneurysms and the remaining 9 were dissecting aneurysms. The mean delay between SAH and treatment was 4.2 days. Intraprocedural and periprocedural morbidity and mortality were recorded. Clinical and angiographic follow-up evaluations were conducted between 6 and 12 months after the procedure. RESULTS None of the ruptured aneurysms re-bled after endovascular treatment. The overall mortality rate was 12% (2/17), involving 2 patients who died after a few days because of complications of SAH. The overall morbidity rate was 12%: 1 patient experienced intraparenchymal bleeding during the repositioning of external ventricular drainage, and 1 patient with a posterior inferior cerebellar artery aneurysm developed paraplegia due to a spinal cord infarction after 2 weeks. The angiographic follow-up evaluations showed a complete occlusion of the aneurysm in 12 of 15 surviving patients; of the 3 remaining cases, 1 patient showed a remnant of the aneurysm, 1 patient was retreated due to an enlargement of the aneurysm, and 1 patient was lost at the angiographic follow-up. CONCLUSIONS FDDs can be used in patients with ruptured aneurysms, where conventional neurosurgical or endovascular treatments can be challenging.

Postprocedural, midterm, and long-term results of cerebral aneurysms treated with flow-diverter devices: 7-year experience at a single center.

OBJECTIVE Flow diversion has emerged as a viable treatment option for selected intracranial aneurysms and recently has been gaining traction. The aim of this study was to evaluate the safety and effectiveness of flow-diverter devices (FDDs) over a long-term follow-up period. METHODS The authors retrospectively reviewed all cerebral aneurysm cases that had been admitted to the Division of Neurosurgery of the Università degli Studi di Napoli between November 2008 and November 2015 and treated with an FDD. The records of 60 patients (48 females and 12 males) harboring 69 cerebral aneurysms were analyzed. The study end points were angiographic evidence of complete aneurysm occlusion, recanalization rate, occlusion of the parent artery, and clinical and radiological evidence of brain ischemia. The occlusion rate was evaluated according to the O'Kelly-Marotta (OKM) Scale for flow diversion, based on the degree of filling (A, total filling; B, subtotal filling; C, entry remnant; D, no filling). Postprocedural, midterm, and long-term results were strictly analyzed. RESULTS Complete occlusion (OKM D) was achieved in 63 (91%) of 69 aneurysms, partial occlusion (OKM C) in 4 (6%), occlusion of the parent artery in 2 (3%). Intraprocedural technical complications occurred in 3 patients (5%). Postprocedural complications occurred in 6 patients (10%), without neurological deficits. At the 12-month follow-up, 3 patients (5%) experienced asymptomatic cerebral infarction. No further complications were observed at later follow-up evaluations (> 24 months). There were no reports of any delayed aneurysm rupture, subarachnoid or intraparenchymal hemorrhage, ischemic complications, or procedure- or device-related deaths. CONCLUSIONS Endovascular treatment with an FDD is a safe treatment for unruptured cerebral aneurysms, resulting in a high rate of occlusion. In the present study, the authors observed effective and stable aneurysm occlusion, even at the long-term follow-up. Data in this study also suggest that ischemic complications can occur at a later stage, particularly at 12-18 months. On the other hand, no other ischemic or hemorrhagic complications occurred beyond 24 months.

Safety and efficacy of aneurysm treatment with WEB: results of the WEBCAST study.

OBJECT WEB is an innovative intrasaccular treatment for intracranial aneurysms. Preliminary series have shown good safety and efficacy. The WEB Clinical Assessment of Intrasaccular Aneurysm Therapy (WEBCAST) trial is a prospective European trial evaluating the safety and efficacy of WEB in wide-neck bifurcation aneurysms. METHODS Patients with wide-neck bifurcation aneurysms for which WEB treatment was indicated were included in this multicentergood clinical practices study. Clinical data including adverse events and clinical status at 1 and 6 months were collected and independently analyzed by a medical monitor. Six-month follow-up digital subtraction angiography was also performed and independently analyzed by a core laboratory. Success was defined at 6 months as complete occlusion or stable neck remnant, no worsening in angiographic appearance from postprocedure, and no retreatment performed or planned. RESULTS Ten European neurointerventional centers enrolled 51 patients with 51 aneurysms. Treatment with WEB was achieved in 48 of 51 aneurysms (94.1%). Adjunctive implants (coils/stents) were used in 4 of 48 aneurysms (8.3%). Thromboembolic events were observed in 9 of 51 patients (17.6%), resulting in a permanent deficit (modified Rankin Scale [mRS] Score 1) in 1 patient (2.0%). Intraoperative rupture was not observed. Morbidity (mRS score > 2) and mortality were 2.0% (1 of 51 patients, related to rupture status on entry to study) and 0.0% at 1 month, respectively. Success was achieved at 6 months in 85.4% of patients treated with WEB: 23 of 41 patients (56.1%) had complete occlusion, 12 of 41 (29.3%) had a neck remnant, and 6 of 41 (14.6%) had an aneurysm remnant. CONCLUSIONS The WEBCAST study showed good procedural and short-term safety of aneurysm treatment with WEB and good 6-month anatomical results.

Blood flow reduction of covered small side branches after flow diverter treatment: a computational fluid hemodynamic quantitative analysis.

Small side branches related brain infarction remains one of the major concerns for flow-diverter devices. However, among several factors, whether this high-profile stent would significantly block blood flow into small side branches remains unclear. The authors quantitatively evaluate blood flow reduction due to the deployment of flow-diverter devices using computational fluid dynamics approach. Thirty one patient-specific anterior inferior cerebellar artery geometries were employed. The flow-diverter device was hypothetically embedded into the basilar trunk, and to cover the anterior inferior cerebellar arteries. The blood flow reduction of each anterior inferior cerebellar artery following flow-diverter device deployment was calculated, with independent validations for both inflow and outflow conditions. Efficient diameters of the anterior inferior cerebellar arteries were calculated to evaluate any correlation with blood flow reduction after flow-diverter devices. The blood flow reduction ratio was shown to be 3.61±1.94%. There was moreover no significant difference of either inflow or outflow boundary conditions during the simulation. The results were calculated approximately as a modest linear correlation between the blood flow reduction ratio and the size of anterior anterior inferior cerebellar arteries which had a mean efficient diameter of 1.12±0.36 mm (range from 0.31 mm to 1.91 mm), and the R(2) was 0.361. When covered by flow-diverter devices, the mechanical blood flow reduction in anterior inferior cerebellar arteries was found to be low with a maximum value estimated to be less than 8%. Therefore, mechanical blood flow reduction is probably not the leading factor contributing to small side branches related brain infarction.

Implantation of two flow diverter devices in a child with a giant, fusiform vertebral artery aneurysm: case report.

BACKGROUND: Intracranial aneurysms in children and adolescents are uncommon; they account for 0.5% to 4.6% of the total intracranial aneurysms cases. METHODS: A 15-year-old boy presented with a 6-month history of occipital headache that worsened over time. A magnetic resonance imaging scan revealed a giant, fusiform aneurysm of the V4 segment of the right vertebral artery with mass effect but no signs of hemorrhage. This lesion was confirmed by the catheter digital subtraction angiography. The posterior inferior cerebellar artery arose from the distal part of the aneurysm. Two flow-diverter devices were implanted in the V4 segment of the right vertebral artery. Follow-up angiograms performed 1 and 2 years after the procedure revealed a total aneurysm occlusion. CONCLUSION: Flow-diverter device implantation may be a viable alternative to parent artery occlusion in a symptomatic, giant, fusiform vertebral artery aneurysm in a child.